Due to the major social problems associated with narcotic abuse, the detection of illicit drugs has become an area of major research. Several broad categories of detection techniques are generally known, including imaging methods, such as x-ray based technologies, the use of trained canines, colorimetric tests and trace chemical detection methods utilizing various “sniffer” technologies. The last category involves indirect detection of a drug by collecting and analyzing minute quantities of vapor or particle contamination. Several technologies have been developed for this type of application, of which ion mobility spectrometry (IMS) is perhaps the most widely utilized.
Drug-facilitated sexual assaults has also become an increasing and concerning problem throughout the world. Drugs used to facilitate rape may have sedative, hypnotic, dissociative, and/or amnesiac effects, and can be readily added to a food or drink without the victim's knowledge. Existing field tests for the so-called “date rape” drugs are not, at best, entirely reliable and sensitive, and cannot be used on all types of drinks due to intrinsic experimental limitations [1-6]. Also, interpretation of the obtained results is often problematic under real-life conditions.
Besides alcohol itself, the most known date-rape drugs are gamma-hydroxybutyrate (GHB), and ketamine. Gamma-hydroxybutyrate (GHB), an ‘easy-to-make’ small endogenous polar compound (C4H8O3), has become the rapist's drug of choice as it has no taste, color or odor, making it hard to detect in a drink GHB is naturally found in trace amounts throughout the human body and is chemically very similar to the neurotransmitter γ-amino butyric acid (GABA).
Initially utilized as an anesthetic, GHB is now employed in narcolepsy, cataplexy and alcohol/opiate withdrawal treatments. However, it is also abused as a recreational drug for its various “desired” effects: euphoria, hallucinations and aphrodisiac. Yet, its adverse effects are all real; aggressive behavior, nausea/vomiting, hallucinations, bradycardia, loss of consciousness, respiratory failure, memory loss and potential death at high doses. When used as a rape-assisting drug, GHB incapacitates the victims, which are usually wrongly diagnosed as “drunk”.
GHB would not be detected on a general drug screening and its detection is only available in specialist laboratories. A key concern with GHB is that there is only a small difference between the dose which leaves the victim unconscious and a dose that may lead to death. A heavy dose is approximately 2.5 grams of GHB. An extra 0.25 grams could be the difference between euphoria and unconsciousness. A dangerous overdose can occur with as little as two grams depending on body weight and the individual's metabolism. Some GHB overdoses lead to unconsciousness, vomiting and a loss of the gag reflex, putting the victim in grave danger of aspiration and death.
Despite the rapid increase in the number of cases in which GHB, and to that extent also ketamine, have been used for abuse, the available methods for detecting the presence of such drugs, particularly GHB, are insensitive, cumbersome and not reliable in detecting these drugs at the required concentrations, in a broad range of alcoholic and non-alcoholic beverages and under real-life conditions. Thus, the development of simple, sensitive and reliable methods for the rapid field detection of ‘date-rape’ drugs in a broad variety of beverages is required.